Tcl

Continue SFTP Keyboard-Interactive Authentication

Demonstrates the Chilkat SFtp.ContinueKeyboardAuth method, which submits a response to a keyboard-interactive prompt. The only argument is the response text; for a request with multiple prompts, an XML response is supplied instead. It returns XML indicating the next prompt or the final result.

Background: This is the second half of the exchange started by StartKeyboardAuth. A server may issue several rounds of prompts, so a robust client loops: submit answers, read the returned XML, and continue until it sees success or failure. On success, remember that InitializeSftp still must be called before any file operation.

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Tcl


load ./chilkat.dll

set success 0

#  Demonstrates the SFtp.ContinueKeyboardAuth method, which submits a response to a
#  keyboard-interactive prompt.  The only argument is the response.  For multiple prompts, an
#  XML response is supplied instead.

set sftp [new_CkSFtp]

#  Step 1: Connect the SSH transport.  Port 22 is the usual port.
set port 22
set success [CkSFtp_Connect $sftp "sftp.example.com" $port]
if {$success == 0} then {
    puts [CkSFtp_lastErrorText $sftp]
    delete_CkSFtp $sftp
    exit
}

#  Begin keyboard-interactive authentication to receive the server's prompt(s).
set infoRequestXml [CkSFtp_startKeyboardAuth $sftp "mySshLogin"]
if {[CkSFtp_get_LastMethodSuccess $sftp] == 0} then {
    puts [CkSFtp_lastErrorText $sftp]
    delete_CkSFtp $sftp
    exit
}

#  Normally you would not hard-code the password in source.  You should instead obtain it
#  from an interactive prompt, environment variable, or a secrets vault.
set password "mySshPassword"

#  Submit the response (typically the password).  The returned XML indicates the next prompt or
#  the final result.
set result [CkSFtp_continueKeyboardAuth $sftp $password]
if {[CkSFtp_get_LastMethodSuccess $sftp] == 0} then {
    puts [CkSFtp_lastErrorText $sftp]
    delete_CkSFtp $sftp
    exit
}

puts "$result"

#  On success, initialize the SFTP subsystem.
set success [CkSFtp_InitializeSftp $sftp]
if {$success == 0} then {
    puts [CkSFtp_lastErrorText $sftp]
    delete_CkSFtp $sftp
    exit
}

CkSFtp_Disconnect $sftp

delete_CkSFtp $sftp